A convenience store owner called 911 on Tuesday when he suspected Powell stole drinks and donuts from his shop, according to a recording of the call. Another woman called to report Powell was acting erratically and had a knife in his pocket.

Two officers in a police SUV responded to the calls, the cell phone video shows. When the officers got out of their vehicle, Powell walked in their direction, yelling and telling them to shoot him already.

St. Louis Police Chief Sam Dotson said Tuesday that both of the officers opened fire on Powell when he came within a three or four feet of them holding a knife "in an overhand grip."

But the newly released cell phone footage undermines the statement, showing Powell approaching the cops, but not coming as close as was reported, with his hands at his side. The officers began shooting within 15 seconds of their arrival, hitting Powell with a barrage of bullets.

The St. Louis Metropolitan Police Department released the video and 911 calls, telling St. Louis Public Radio that it plans to act transparently.

The shooting death occurred less than four miles from where Michael Brown was fatally shot by a police officer in the suburb of Ferguson on Aug. 9.

The St. Louis Police Department did not immediately respond to a request for comment from The Huffington Post. [See UPDATE below.]

Dotson defended the officers in a television appearance later Wednesday, acknowledging the discrepancies between his Tuesday account and what the video revealed. Though Powell's hands were down by his sides, Dotson told CNN, he was moving toward the officer with a knife.

"The officers did what I think you or I would do, they protected their life in that situation," Dotson said.

CNN's Don Lemon and Chris Cuomo pushed Dotson on the officers' decision to use lethal force, rather than opting for an alternate form of defense like a Taser.

"Certainly a Taser is an option that's available to the officers, but Tasers aren't 100 percent," Dotson said. "So you've got an individual with a knife who's moving towards you, not listening to any verbal commands, continues, says, 'shoot me now, kill me now.' Tasers aren't 100 percent. if that Taser misses, that [individual] continues on and hurts an officer."

"In a lethal situation, they used lethal force," he added.

Listen to the 911 calls at St. Louis Public Radio, and watch the video below. Note that both contain graphic images and language.

Warning: The below video includes graphic content.

UPDATE: Aug. 22, 5 p.m. -- "On the day of the officer-involved shooting, Chief Dotson briefed the media at the scene and provided information given to him by witnesses, not the officers," Schron Jackson, spokesperson for the St. Louis police, told HuffPost. "Witnesses reported the suspect held the knife in an over-hand grip. After reading the officers' statements, the next day, Chief Dotson called a press conference to inform the media/community of the officers account of the incident. It's not uncommon for initial reports to have inaccuracies, witnesses at different angles see different things. Chief Dotson was being open and transparent in releasing the video to the media/community."

Jackson added that Powell was indeed holding a knife, which was recovered at the scene.